Liquid-crystal display device having paired sub-pixel electrodes

ABSTRACT

A liquid-crystal display device includes a first substrate, a plurality of pixel units disposed on the first substrate, a color filter layer overlapping the plurality of pixel units and including first to third color filters, a second substrate facing the first substrate, and a liquid-crystal layer interposed between the first substrate and the second substrate. Each of the pixel units of the plurality of the pixel units includes a first pixel, a second pixel and a third pixel. The first pixel includes a first pixel electrode, the second pixel includes a second pixel electrode, and the third pixel includes a first sub-pixel electrode and a second sub-pixel electrode. A voltage applied to the first sub-pixel electrode is different from a voltage applied to the second sub-pixel electrode.

This application claims priority under 35 USC § 119 to Korean PatentApplication No. 10-2016-0030294 filed on Mar. 14, 2016 in the KoreanIntellectual Property Office, the disclosure of which is incorporated byreference herein in its entirety.

TECHNICAL FIELD

The present disclosure relates to a liquid-crystal display (LCD) deviceand, more particularly, to a liquid-crystal display (LCD) device capableof improving visibility without reducing transmittance.

DISCUSSION OF THE RELATED ART

A liquid-crystal display (LCD) device is a commonly used type of flatpanel display device. An LCD device may include two substrates on whichfield generating electrodes such as a pixel electrode and a commonelectrode may be disposed, and a liquid-crystal layer. Theliquid-crystal layer may be disposed between the pixel electrode and thecommon electrode. An LCD device displays an image by applying a voltageto the field generating electrodes to generate an electric field acrossthe liquid-crystal layer. Further, liquid-crystal molecules in theliquid-crystal layer are aligned by the electric field so as to controlpolarization of incident light.

Among other alignment modes, a vertically aligned (VA) mode in an LCD isunder development. A VA mode LCD orients the liquid crystal moleculessuch that their major axes are perpendicular to the upper and lowersubstrates when no electric field is applied.

In such a VA mode of an LCD device, a plurality of domains withdifferent orientations of liquid crystals may be formed in a pixel toachieve wide viewing angle.

To form such a plurality of domains, cut portions such as fine slits maybe formed in the field generating electrodes or protrusions may beformed on the field generating electrodes.

SUMMARY

Aspects of the present inventive concept provide an LCD device that mayimprove visibility without reducing transmittance.

According to an exemplary embodiment of the present inventive concept, aliquid-crystal display (LCD) device includes a first substrate, aplurality of pixel units disposed on the first substrate, a color filterlayer overlapping the plurality of pixel units and including first tothird color filters. The LCD device further includes a second substratefacing the first substrate, and a liquid-crystal layer interposedbetween the first substrate and the second substrate. Each of the pixelunits of the plurality of the pixel units includes a first pixel, asecond pixel and a third pixel. The first pixel includes a first pixelelectrode, the second pixel includes a second pixel electrode, and thethird pixel includes a first sub-pixel electrode and a second sub-pixelelectrode. The first color filter overlaps the first pixel electrode,the second color filter overlaps the second pixel electrode, and thethird color filter overlaps each of the first sub-pixel electrode andthe second sub-pixel electrode. A voltage applied to the first sub-pixelelectrode is different from a voltage applied to the second sub-pixelelectrode. Each of the first pixel, the second pixel and the third pixelhas substantially a same area.

According to an exemplary embodiment of the present inventive concept, aliquid-crystal display (LCD) device includes a first substrate, aplurality of pixel units disposed on the first substrate, a color filterlayer overlapping the plurality of pixel units and including first tothird color filters. The LCD device further includes a second substratefacing the first substrate, and a liquid-crystal layer interposedbetween the first substrate and the second substrate. Each of the pixelunits of the plurality of the pixel units includes first to fourthpixels. The first pixel includes a first pixel electrode, the secondpixel includes a second pixel electrode, the third pixel includes athird pixel electrode, and the fourth pixel includes a fourth pixelelectrode. The first color filter overlaps the first pixel electrode,the second color filter overlaps the second pixel electrode, and thethird color filter overlaps both of the third and fourth pixelelectrodes. A voltage applied to the third pixel electrode is differentfrom a voltage applied to the fourth pixel electrode. In each of thepixel units, an area occupied by the first pixel, an area occupied bythe second pixel, a sum of an area occupied by the third pixel, and anarea occupied by the fourth pixel are all substantially equal to oneanother.

According to an exemplary embodiment of the present inventive concept, aliquid-crystal display (LCD) device includes a first substrate, aplurality of pixel units disposed on the first substrate, a secondsubstrate facing the first substrate, a liquid-crystal layer interposedbetween the first substrate and the second substrate, and a blue colorfilter. Each of the pixel units of the plurality of the pixel unitsincludes first to fourth pixels. The first pixel includes a first pixelelectrode, the second pixel includes a second pixel electrode, the thirdpixel includes a third pixel electrode, and the fourth pixel includes afourth pixel electrode. The blue color filter overlaps both the thirdand fourth pixel electrodes. A voltage applied to the third pixelelectrode is different from a voltage applied to the fourth pixelelectrode.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects and features of the present inventiveconcept will become more apparent by describing in detail exemplaryembodiments thereof with reference to the accompanying drawings, inwhich:

FIG. 1 is a block diagram of a liquid-crystal display (LCD) deviceaccording to an exemplary embodiment of the present inventive concept;

FIG. 2 is a layout diagram of a single pixel disposed in a display panelaccording to an exemplary embodiment of the present inventive concept;

FIG. 3 is a cross-sectional view taken along line I-I′ of FIG. 2;

FIG. 4 is a view schematically showing pixel units according to anexemplary embodiment of the present inventive concept;

FIG. 5 is a graph showing brightness versus grayscale level of an LCDdevice according to an exemplary embodiment of the present inventiveconcept;

FIG. 6 is a xy chromaticity diagram showing color gamut of aliquid-crystal display (LCD) device according to an exemplary embodimentof the present inventive concept;

FIG. 7 is a layout diagram of a single pixel disposed in a display panelaccording to an exemplary embodiment of the present inventive concept;

FIG. 8 is a view schematically showing pixel units of an exemplaryembodiment of the present inventive concept shown in FIG. 7;

FIG. 9 is a layout diagram of a single pixel disposed in a display panelaccording to an exemplary embodiment of the present inventive concept;

FIG. 10 is a view schematically showing pixel units of an exemplaryembodiment of the present inventive concept shown in FIG. 9; and

FIG. 11 is a layout diagram of a single pixel disposed in a displaypanel according to an exemplary embodiment of the present inventiveconcept.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Exemplary embodiments of the present invention will be described in moredetail below with reference to the accompanying drawings, in whichexemplary embodiments of the preset invention are shown. The samereference numbers may indicate the same components throughout thespecification. In the accompanying figures, the thickness of layers andregions may be exaggerated for clarity.

Spatially relative terms, such as “beneath,” “below,” “lower,” “above,”“upper” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is turned over, elements described as “below” or “beneath” otherelements or features would then be oriented “above” the other elementsor features. Thus, the exemplary term “below” can encompass both anorientation of above and below. The device may be otherwise oriented(rotated 90 degrees or at other orientations) and the spatially relativedescriptors used herein may be interpreted accordingly.

It will be understood that the terms “first,” “second,” “third,” etc.are used herein to distinguish one element from another, and theelements are not limited by these terms. Thus, a “first” element in anexemplary embodiment may be described as a “second” element in anotherexemplary embodiment.

In the present inventive concept, an electronic apparatus may be anyapparatus provided with a display device. Examples of the electronicapparatus may include smartphones, mobile phones, navigators guidancedevice, game console, televisions, car head units, notebook computers,laptop computers, tablet computers, personal media players (PMPs),personal digital assistants (PDAs), etc. The electronic apparatus may beembodied as a pocket-sized portable communication terminal having awireless communication function. Further, the display device may be aflexible display device capable of bending or folding.

Hereinafter, exemplary embodiments of the present inventive concept willbe described with reference to the accompanying drawings.

FIG. 1 is a block diagram of a liquid-crystal display (LCD) deviceaccording to an exemplary embodiment of the present inventive concept.

Referring to FIG. 1, the LCD device according to an exemplary embodimentof the present inventive concept may include a display panel 100, a gatedriver 110, a data driver 120 and a signal controller 130.

The display panel 100 includes a display area DA where a plurality ofpixel units PXUs is disposed, and a non-display area NDA that may beoutside of the display area DA.

The display area DA includes the plurality of pixel units PXUs arrangedin a matrix. Each of the pixel units PXUs may be a minimum unit forreproducing an arbitrary color and each pixel unit PXU may include aplurality of pixels PXs. A color reproduced by a pixel unit PXU may bedetermined by a combination of colors of a plurality of pixels PXsincluded in the pixel unit PXU. For example, of the pixel units PXUs mayinclude three pixels PXs. The three pixels may include a pixel PX forproducing red color, a pixel PX for producing green color, and a pixelPX for producing blue color. A pixel PX may represent a color determinedby a color of a color filter layer to be described below, and the pixelunit PXU may be the minimum unit for controlling grayscale.

The non-display area NDA may surround the outer periphery of the displayarea DA. Further, elements for driving the pixels PXs may be disposed inthe non-display area NDA. Examples of the elements for driving thepixels PXs in the display area DA may include the gate driver 110, thedata driver 120 and the signal controller 130.

The display panel 100 may include a plurality of gate lines 224extending in a first direction D1 (e.g., an x-axis direction), and aplurality of data lines 267 extending in a second direction D2 (e.g., ay-axis direction). The first direction D1 crosses the second directionD2.

The gate lines 224 may receive gate signals from the gate driver 110,and the data lines 267 may receive data signals from the date driver120. Each of the pixels PXs may be connected to the gate lines 224 andthe data lines 267 to receive the gate signals and the data signals.

The signal controller 130 may receive a variety of signals from externalsources and may control the gate driver 110 and the data driver 120. Thesignal controller 130 may receive first image data DATA1 and an inputcontrol signals CONT1 for controlling how to display the first imagedata DATA1. Further, the signal controller 130 may output a gate drivercontrol signal CONT3, a data driver control signal CONT2, second imagedata DATA2, etc.

The first image data DATA1 may contain brightness information for eachof the pixels PXs. The brightness information may have a predeterminednumber of gray levels, for example, 1,024 (=2¹⁰), 256 (=2⁸) or 64 (=2⁶)gray levels. The received first image data DATA1 may be divided frame byframe.

The input control signal CONT1 delivered to the signal controller 130may include, for example, a vertical synchronous signal Vsync, ahorizontal synchronous signal Hsync, a main clock signal Mclk and a dataenable signal DE. However, exemplary embodiments of the presentinventive concept are not limited thereto. For example, other types ofsignals may further be inputted to the signal controller 130.

The gate driver control signal CONT3 may control the operation of thegate driver 110 and may be generated in the signal controller 130. Thesignal controller 130 may provide the gate driver control signal CONT3to the gate driver 110. The gate driver control signal CONT3 mayinclude, but is not limited to, a scan start signal, a clock signal,etc. The gate driver 110 may generate the gate signals for activatingthe pixels PXs in response to the gate driver control signal CONT3 andmay provide each of the gate signals to the respective gate lines 224 ofthe pixels PXs.

The data driver control signal CONT2 may control the operation of thedata driver 120 and may be generated in the signal controller 130. Thesignal controller 130 may provide the data driver control signal CONT2to the data driver 120. The data driver 120 may generate the datasignals in response to the data driver control signal CONT2 and mayprovide each of the data signals to the respective data lines 267 of thepixels PXs.

Hereinafter, a structure of a pixel unit PXU will be described withreference to FIGS. 2 and 3.

FIG. 2 is a layout diagram of a single pixel disposed in a display panelaccording to an exemplary embodiment of the present inventive concept.FIG. 3 is a cross-sectional view taken along line I-I′ of FIG. 2.

Referring to FIGS. 2 to 3, a display panel 100 according to an exemplaryembodiment of the present inventive concept may include an arraysubstrate 200, an opposing substrate 400 and a liquid-crystal layer 300.

On the array substrate 200, first to third thin-film transistors TR1,TR2 and TR3 are disposed. The first to third thin-film transistors TR1,TR2 and TR3 work as switching elements for applying the data voltage toa pixel PX. The opposing substrate 400 is disposed such that it facesthe array substrate 200. For example, the opposing substrate 400 may bedisposed above or below the array substrate 200. The liquid-crystallayer 300 may be disposed between the array substrate 200 and theopposing substrate 400. In the liquid crystal layer 300, liquid crystals310 may be injected.

Hereinafter, the array substrate 200 will be described.

The array substrate 200 may include a first base substrate 210. Thefirst base substrate 210 may be, for example, a transparent insulationsubstrate. For example, the first base substrate 210 may be a glasssubstrate, a quartz substrate, a transparent resin substrate, etc.

In an exemplary embodiment of the present inventive concept, the firstbase substrate 210 may be curved in a particular direction. In anexemplary embodiment of the present inventive concept, the first basesubstrate 210 may be flexible. For example, the first base substrate 210may be deformable so that it may be rolled, folded, bent and so on.

A plurality of gate lines 224, a first gate electrode 221, a second gateelectrode 222, and a third gate electrode 223 may be disposed on thefirst base substrate 210.

The gate lines 224 may deliver gate signals and may be extended in afirst direction D1.

As used herein, the first direction D1 refers to a direction extendingin parallel with a side of the first base substrate 210. In FIG. 2, theside of the first base substrate 210 that extends parallel to the firstdirection D1 may extend from a left side to a right side. For example,as shown in FIG. 2, the first direction D1 may be defined as a directionindicated by a straight line extending from the left side to the rightside. However, the first direction D1 is not limited to being inparallel with a side of the first base substrate 210. The firstdirection D1 may be a direction indicated by any straight line extendingin any direction.

The gate signals may each have a varying voltage value provided from anexternal source, and the thin-film transistors TR1, TR2 and TR3, to bedescribed below, may be turned on/off in response to the voltage valueof the gate signals.

The first to third gate electrodes 221, 222 and 223 may protrude fromthe gate line 224 and may be elements of the first, second and thirdthin-film transistors TR1, TR2 and TR3, respectively.

In the gate line 224, a plurality of first gate electrodes 221, aplurality of second gate electrodes 222, and a plurality of third gateelectrode 223 may be formed. The arrangement of the first to third gateelectrodes 221, 222 and 223 will be described below in describing thefirst to third thin-film transistors TR1, TR2 and TR3.

The gate line 224 and the first to third gate electrodes 221, 222 and223 may include: an aluminum-based metal such as aluminum (Al) or analuminum alloy; a silver-based metal such as silver (Ag) or a silveralloy; a copper-based metal such as copper (Cu) or a copper alloy; agold-based metal such as gold (Au) or a gold alloy; a molybdenum-basedmetal such as molybdenum (Mo) or a molybdenum alloy; chromium (Cr);tantalum (Ta); or titanium (Ti). The gate line 224 and the first tothird gate electrodes 221, 222 and 223 may be a single layer structure.Alternatively, the gate line 224 and the first to third gate electrodes221, 222 and 223 may be a multi-layer structure including at least twoconductive films having different physical properties.

As described above with reference to FIG. 1, a pixel unit PXU mayinclude a plurality of pixels PXs. In an exemplary embodiment of thepresent inventive concept, a pixel unit PXU includes three pixels PXs,for example. They are referred to as a first pixel PX1, a second pixelPX2 and a third pixel PX3. It is to be noted that each of the firstpixel PX1 and the second pixel PX2 may include the first gate electrode221 while the third pixel PX3 includes each of the first to third gateelectrodes 221, 222 and 223.

A gate insulation film 230 may be disposed on the gate line 224 and thefirst to third gate electrodes 221, 222 and 223. The gate insulationfilm 230 may be made of an insulative material, for example, siliconnitride or silicon oxide. The gate insulation film 230 may be a singlelayer structure or may be a multi-layer structure, which may include twoinsulation layers having different physical properties from each other.

First to third semiconductor layers 241, 242 and 243 may be disposed onthe gate insulation film 230. The first semiconductor layer 241 mayoverlap at least a part of the first gate electrode 221. The secondsemiconductor layer 242 may overlap at least a part of the second gateelectrode 222. The third semiconductor layer 243 may overlap at least apart of the third gate electrode 223. The first to third semiconductorlayers 241, 242 and 243 may include amorphous silicon, polycrystallinesilicon or an oxide semiconductor.

The first to third semiconductor layers 241, 242 and 243 may overlap atleast a part of a data line 267, first to third source electrodes 261,262 and 263 to, and/or the first to third gate electrodes 221, 222 and223.

Although not shown in the drawings, in an exemplary embodiment of thepresent inventive concept, an ohmic contact element may be disposed onthe first to third semiconductor layers 241, 242 and 243. The ohmiccontact element may be made of n+ hydrogenated amorphous silicon that ishighly doped with n-type impurities, or may be made of silicide. Forexample, a pair of the ohmic contact elements may be disposed on thefirst to third semiconductor layers 241, 242 and 243. The ohmic contactelements may allow the electric connection between the first, second andthird semiconductor layers 241, 242 and 243 and other elementselectrically connected to the first, second and third semiconductorlayers 241, 242 and 243 to have ohmic contact properties.

Further, the data line 267, first to third source electrodes 261, 262and 263, first to third drain electrodes 264, 265 and 266, and a storageline 268 may be disposed on the first to third semiconductor layers 241,242 and 243 and the gate insulation film 230.

The data line 267 may extend in a second direction D2 and may intersectthe gate line 224.

Herein, the second direction D2 may be a direction intersecting thefirst direction D1 on a plane (e.g., an x-y plane), for example, a planethat faces the base substrate 210. However, exemplary embodiments of thepresent inventive concept are not limited thereto. The angle made by thesecond direction D2 intersecting the first direction D1 might not be aright angle. For example, the second direction D2 may be a directionthat does not extend in a direction that extend in a direction parallelwith the first direction D1.

The data line 267 may be insulated from the gate line 224 by the gateinsulation film 230.

The data line 267 may provide the data signal to the first and secondsource electrodes 261 and 262. The data signal may have a varyingvoltage value provided from an external source, and the gray scale ofeach of the first to third pixels PX1, PX2 and PX3 may be controlled inresponse to the data signal.

The first source electrode 261 may be electrically connected to the dataline 267 and may overlap at least a part of the first gate electrode221. In addition, the second source electrode 262 may be electricallyconnected to the first source electrode 261 and may overlap at least apart of the second gate electrode 222. In an exemplary embodiment of thepresent inventive concept, the second electrode 262 may be electricallyconnected to the data line 267, instead of the first source electrode261.

The storage line 268 may be extended in the second direction D2 and mayintersect the gate line 224. The storage line 268 may be formed in thesame layer as the data line 267 and might not overlap with the data line267. The storage line 268 may be insulated from the gate line 224 by thegate insulation film 230. The gate insulation film 230 may be disposedbetween the storage line 268 and the gate line 224.

The storage line 268 may provide a storage signal input from an externalsource to the third source electrode 263. The storage signal may have aconstant voltage value provided from the external source and may have avoltage value smaller than a maximum voltage value and larger than aminimum voltage value of the varying voltage value of the data signal.

The third source electrode 263 may be electrically connected to thestorage line 268 and may overlap at least a part of the third gateelectrode 223.

The first drain electrode 264 may be spaced apart from the first sourceelectrode 261 with the first semiconductor layer 241 disposedtherebetween. The first drain electrode 264 and the first sourceelectrode 261 may each overlap at least a part of the first gateelectrode 221. The second drain electrode 265 may be spaced apart fromthe second source electrode 262 with the second semiconductor layer 242disposed therebetween. The second drain electrode 265 and second sourceelectrode 262 may each overlap at least a part of the second gateelectrode 222. The third drain electrode 266 may be spaced apart fromthe third source electrode 263 with the third semiconductor layer 243disposed therebetween and may overlap at least a part of the third gateelectrode 223. As shown in FIG. 2, the first to third source electrodes261, 262 and 263 may have a shape similar to a U-shape such that thefirst, second and third source electrodes 261, 262 and 263 each surroundthe first, second and third drain electrodes 264, 265 and 266,respectively. Further, gaps may also exist between the first sourceelectrode 261 and the second source electrode 261, between the secondsource electrode 262 and the third source electrode 263, between thefirst drain electrode 264 and the second drain electrode 265, andbetween the second drain electrode 265 and the third drain electrode266. However, exemplary embodiments of the present inventive concept arenot limited thereto. In addition, the first to third source electrodes261, 262 and 263 may have a rod-like shape such that they may bedisposed in parallel with the first to third drain electrodes 264, 265and 266, respectively. Further, a gap may also, respectively, existbetween the first to third source electrodes 261, 262 and 263 and thefirst to third drain electrodes 264, 265 and 266.

The first semiconductor layer 241 may be disposed between the firstsource electrode 261 and the first drain electrode 264, which isseparated from the first source electrode 261. For example, the firstsource electrode 261 and the first drain electrode 264 may partiallyoverlap or come in contact with the first semiconductor layer 241.Further, the first source electrode 261 and the first drain electrode264 may each be disposed on opposite ends from each other on the firstsemiconductor layer 241. The first semiconductor layer 241 may bedisposed between the first source electrode 261 and the first drainelectrode 264. A similar arrangement applies to the second drainelectrode 265, the second source electrode 262 and the secondsemiconductor layer 242, and to the third drain electrode 266, the thirdsource electrode 263 and the third semiconductor layer 243.

The data line 267, the storage line 268, the first to third sourceelectrodes 261, 262 and 263, the first to third drain electrodes 264,265 and 266 may include aluminum, copper, silver, molybdenum, chrome,titanium, tantalum or an alloy thereof. In addition, the aforementionedlines and electrodes have a multi-layer structure composed of a lowerlayer such as a refractory metal, and a low-resistance upper layerdisposed on the lower layer. However, other configurations may be used.

The first gate electrode 221, the first semiconductor layer 241, thefirst source electrode 261 and the first drain electrode 264 form thefirst thin-film transistor TR1. The second gate electrode 222, thesecond semiconductor layer 242, the second source electrode 262 and thesecond drain electrode 265 form the second thin-film transistor TR2. Thethird gate electrode 223, the third semiconductor layer 243, the thirdsource electrode 263 and the third drain electrode 266 form the secondthin-film transistor TR3.

The first thin-film transistor TR1 may electrically connect the firstsource electrode 261 to the first drain electrode 264 in response to avoltage value of the gate signal supplied to the first gate electrode221. For example, if the voltage value of the gate signal supplied tothe first gate electrode 221 reaches the voltage value to turn off thefirst thin-film transistor TR1, the first source electrode 261 and thefirst drain electrode 264 may be electrically insulated from each other.Further, if the voltage value of the gate signal supplied to the firstgate electrode 221 reaches the voltage value to turn on the firstthin-film transistor TR1, the first source electrode 261 and the firstdrain electrode 264 may be electrically connected to each other via achannel formed in the first semiconductor layer 241.

The channel may be formed in the first semiconductor layer 241 betweenthe first source electrode 261 and the first drain electrode 264. Forexample, when the first thin-film transistor TR1 is in an on-state, thechannel is formed in the first semiconductor layer 241 disposed betweenthe first source electrode 261 and the first drain electrode 264, andthe voltage of the data signal may be delivered from the first sourceelectrode 261 to the first drain electrode 264 along the channel.

The data signal delivered to the first drain electrode 264 may bedelivered to a first pixel electrode 283, a second pixel electrode 284,or a first sub-pixel electrode 285. Accordingly, the data signal may ormight not be delivered depending on the gate signal supplied to the gateline 224. The first pixel electrode 283, the second pixel electrode 284and the first sub-pixel electrode 285 will be described below.

Likewise, the second thin-film transistor TR2 may electrically connectthe second source electrode 262 to the second drain electrode 265 inresponse to a voltage value of the gate signal supplied to the secondgate electrode 222. Accordingly, the data signal supplied to the dataline 267 is delivered to a second sub-pixel electrode 286 connected tothe second drain electrode 265 via the second drain electrode 265.

In addition, the third thin-film transistor TR3 may electrically connectthe third source electrode 263 to the third drain electrode 266 inresponse to a voltage value of the gate signal supplied to the thirdgate electrode 223. Accordingly, the storage signal supplied to thestorage line 268 is delivered to a second sub-pixel electrode 286connected to the third drain electrode 266 via the third drain electrode266.

Unlike the first and second pixel electrodes 283 and 284 and the firstsub-pixel electrode 285 that may all receive the data signal only fromthe first drain electrode 264, the second sub-pixel electrode 286 mayreceive the data signal from the second drain electrode 265 and mayreceive the storage signal from the third drain electrode 266.Accordingly, the voltage value corresponding to the data signal may beprovided to the first pixel electrode 283, the second pixel electrode284 and the first sub-pixel electrode 285, but one voltage value betweenthe voltage value of the data signal and the voltage value of thestorage signal may be provided to the second sub-pixel electrode 286.

The one voltage value between the voltage value of the data signal andthe voltage value of the storage signal may refer to any voltage valuethat is smaller than the voltage value of the data signal and largerthan the voltage value of the storage signal. In addition, the onevoltage value between the voltage value of the data signal and thevoltage value of the storage signal may refer to any voltage value thatis larger than the voltage value of the data signal and smaller than thevoltage value of the storage signal. The one voltage value between thevoltage value of the data signal and the voltage value of the storagesignal may be determined based on the spacing between the second sourceelectrode 262 and the second drain electrode 265 and based on thespacing between the third source electrode 263 and the third drainelectrode 266.

Therefore, each of the first pixel PX1 and the second pixel PX2 includesthe first thin-film transistor TR1 only, while the third pixel PX3includes the first to third thin-film transistors TR1, TR2 and TR3.

Accordingly, the first pixel PX1 includes the first pixel electrode 283,and the tilt angle of the liquid crystals 310 disposed in the firstpixel PX1 may be determined based on the voltage applied to the firstpixel electrode 283. Further, the second pixel PX2 includes the secondpixel electrode 284, and the tilt angle of the liquid crystals 310disposed in the second pixel PX2 is determined based on the voltageapplied to the second pixel electrode 284.

Further, the third pixel PX3 includes the first sub-pixel electrode 285,the second sub-pixel electrode 286, and the first to third thin-filmtransistors TR1, TR2 and TR3, such that different voltages may beapplied to the first sub-pixel electrode 285 and the second sub-pixelelectrode 286. Accordingly, the tilt angle of some of the liquidcrystals 310 disposed in the third pixel PX3 may be determined based onthe voltage applied to the first sub-pixel electrode 285, and the tiltangle of the other of the liquid crystals 310 in the third pixel PX3 maybe determined based on the voltage applied to the second sub-pixelelectrode 286.

Based on the above-described structure of the third pixel PX3, thevisibility of the LCD device may be increased. For example, if the thirdpixel PX3 is a pixel PX for producing blue color, the visibility of theLCD device may be increased when a skin color is being displayed in animage.

In addition, unlike the third pixel PX3 including the first to thirdthin-film transistors TR1, TR2 and TR3, each of the first pixel PX1 andthe second pixel PX2 includes the thin-film transistor TR1 and does notinclude the second and third thin-film transistors TR2 and TR3. Thus, areduction in transmittance of a pixel may be avoided.

In addition, the first to third pixels PX1, PX2 and PX3 included in asingle pixel unit PXU may be controlled by the same gate line 224.Accordingly, the first thin-film transistor TR1 included in the firstpixel PX1, the first thin-film transistor TR1 included in the secondpixel PX2, and the first to third thin-film transistors TR1, TR2 and TR3included in the third pixel PX3 may be arranged in parallel in thesecond direction D2 along the same gate line 224.

A passivation layer 271 may be disposed on the gate insulation film 230and the first to third thin-film transistors TR1, TR2 and TR3. Thepassivation layer 271 may be made of, for example, an inorganicinsulative material and may, for example, cover the first to thirdthin-film transistors TR1, TR2 and TR3. The passivation layer 271 mayprotect the first to third thin-film transistors TR1, TR2 and TR3 fromother elements and impurities that may be disposed over the first tothird thin-film transistors TR1, TR2 and TR3.

A planarization layer 272 may be disposed on the passivation layer 271.The planarization layer 272 may provide a flat surface above thepassivation layer 271. The planarization layer 272 may be made of, forexample, an organic material. In an exemplary embodiment of the presentinventive concept, the planarization layer 272 may be made of aphotosensitive organic composition. In an exemplary embodiment of thepresent inventive concept, the planarization layer 272 may be made of aphotosensitive organic composition containing a pigment for reproducinga color, or an additional photosensitive organic composition layer maybe disposed under the planarization layer 272. In either case, thepigment works as the color filter layer and, thus, use of the pigmentmay eliminate the need for the color filter layer of the opposingsubstrate 400 to be described later.

The passivation layer 271 and/or the planarization layer 272 may beomitted.

Further, first and second contact holes 281 and 282 may be formed in theplanarization layer 272 and the passivation layer 271 such that a partof each of the first to third thin-film transistors TR1, TR2 and TR3 maybe exposed. Further, the part exposed may be part of each of the firstto third drain electrodes 264, 265 and 266, respectively.

The first contact hole 281 may vertically penetrate the planarizationlayer 272 and the passivation layer 271. The first contact hole 281 mayexpose a part of the first drain electrode 264.

The second contact hole 282 may vertically penetrate the planarizationlayer 272 and the passivation layer 271. The second contact hole 282 mayexpose a part of each of the second drain electrode 265 and the thirddrain electrode 266.

The first pixel electrode 283, the second pixel electrode 284, the firstsub-pixel electrode 285 and the second sub-pixel electrode 286 may bedisposed on the planarization layer 272. The first pixel electrode 283,the second pixel electrode 284 and the first sub-pixel electrode 285 maybe connected to the first drain electrode 264 via the first contact hole281 to receive voltage from the first drain electrode 264. The secondsub-pixel electrode 286 may be connected to the second and third drainelectrodes 265 and 266 via the second contact hole 282 to receivevoltage from the second drain electrode 265 and voltage from third drainelectrodes 266.

The first pixel electrode 283 may be disposed in the first pixel PX1,and the second pixel electrode 284 may be disposed in the second pixelPX2. The first pixel electrode 283 and the second pixel electrode 284may have substantially the same shape as each other. However, the areaoccupied by the first sub-pixel electrode 285 may be smaller than theareas occupied by the first pixel electrode 283. Further, the areaoccupied by the first sub-pixel electrode 285 may be smaller than thatof the second pixel electrode 284. Unlike the first pixel PX1 and thesecond pixel PX2 may be disposed alone in the first pixel electrode 283and the second pixel electrode 284. The first sub-pixel electrode 285may be disposed in the third pixel PX3 along with the second sub-pixelelectrode 286. The sum of the area occupied by the first sub-pixelelectrode 285 and the area occupied by the second sub-pixel electrode286 may be equal to or less than the area occupied by the first pixelelectrode 283 or the area occupied by the second pixel electrode 284.

Each of the first pixel electrode 283, the second pixel electrode 284,the first sub-pixel electrode 285, and the second sub-pixel electrode286 may be made of, for example, a transparent conductive material suchas indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zincoxide (ITZO), Al-doped zinc oxide (AZO).

The first pixel electrode 283 may be disposed in the first pixel PX1such that the first pixel electrode 283 forms fine slits in the firstpixel PX1 and may form four domains to increase visibility. The secondpixel electrode 284 may be disposed, in a similar manner, in the secondpixel PX2.

The first sub-pixel electrode 285 and the second sub-pixel electrode 286may be disposed in the third pixel PX3 by forming a pattern in the thirdpixel PX3. The first sub-pixel electrode 285 along with the secondsub-pixel electrode 286 may form four domains. However, the voltageapplied to the first sub-pixel electrode 285 may be different from thevoltage applied to the second sub-pixel electrode 286. Further, thefirst sub-pixel electrode 285 may be separated from the second sub-pixelelectrode 286. For example, the second sub-pixel electrode 286 maysurround the first sub-pixel electrode 285. The first sub-pixelelectrode 285 may be connected to the first thin-film transistor TR1.The second sub-pixel electrode 286 may be connected to the second andthird thin-film transistors TR2 and TR3.

An alignment layer 290 may be disposed on the first pixel electrode 283,the second pixel electrode 284, the first sub-pixel electrode 285 andthe second sub-pixel electrode 286. The first alignment layer 290 maycontrol an initial orientation of the liquid crystals 310 that areinjected into the liquid-crystal layer 300. The first alignment layer290 may be omitted.

Hereinafter, the opposing substrate 400 will be described.

The opposing substrate 400 may include a second base substrate 410, alight-blocking element 420, a common electrode 480, an overcoat layer440 and a second alignment layer 490.

The second base substrate 410 may be disposed such that it faces thefirst base substrate 210. The second base substrate 410 may besufficiently durable so as to withstand an external impact. The secondbase substrate 410 may be a transparent insulation substrate. Forexample, the second base substrate 410 may be a glass substrate, aquartz substrate, a transparent resin substrate, etc. The second basesubstrate 410 may be a flat plate, although it may be curved in aparticular direction. In an exemplary embodiment of the presentinventive concept, the second base substrate 410 may be flexible. Forexample, the second base substrate 410 may be deformable so that it maybe rolled, folded, bent and so on.

The light-blocking element 420 may be disposed on the liquid crystallayer 300. The light-blocking element 420 may be disposed such that itoverlaps the data line 267, the gate line 224, the first to thirdthin-film transistor TR1, TR2 and TR3 and the first and second contactholes 281 and 282, thereby blocking light from leaking when the liquidcrystals 310 are misaligned. For example, since each of the first pixelPX1 and the second pixel PX2 does not include the second and thirdthin-film transistors TR2 and TR3, unlike the third pixel PX3, the areaoccupied by the light-blocking element 420 in each of the first pixelPX1 and the second pixel PX2 may be smaller than the area occupied bythe light-blocking element 420 in the third pixel PX3. Accordingly, thetransmittance may be reduced less compared to an LCD device in whicheach of the first to third pixels PX1, PX2 and PX3 includes the first tothird thin-film transistors TR1, TR2 and TR3.

The color filter layer may be disposed on the second base substrate 410and the light-blocking element 420. For example, the color filter may bedisposed below the second base substrate 410. The color filter layer mayallow a particular wavelength of a light that comes through the firstbase substrate 210 to exit through the second base substrate 410, suchthat the light has a particular color.

The color filter layer may be made of a photosensitive organiccomposition containing a pigment for reproducing a color and may includeeither red, green or blue pigments.

Each of the pixels PXs may include the color filter layer. In anexemplary embodiment of the present inventive concept, the color filterlayer may include a first color filter 431 disposed in the first pixelPX1, a second color filter disposed in the second pixel PX2, and a thirdcolor filter disposed in the third pixel PX3.

The first color filter 431 may be a red color filter that allows a lightpassing therethrough to have red color. The second color filter may be agreen color filter that allows a light passing therethrough to havegreen color. The third color filter may be a blue color filter thatallows a light passing therethrough to have blue color.

However, exemplary embodiments of the present inventive concept are notlimited thereto. For example, first color filter 431 may be a greencolor filter, and the second color filter may be a red color filter.However, in the pixel PX3 including the second and third thin-filmtransistors TR2 and TR3, a blue color filter is disposed.

The transmittance of the third pixel PX3 in which the liquid crystals310 are controlled at two or more tilt angles may be lower than thetransmittance of each of the first pixel PX1 and the second pixel PX2 inwhich the liquid crystals 310 are controlled at one tilt angle. Thelower transmittance may be caused by the third pixel PX3 in which theliquid crystals 310 controlled at two or more tilt angles, requiringmore elements, e.g., the second thin-film transistor TR2 and the thirdthin-film transistor TR3.

In this regard, the red and green color filters contribute to colorreproduction more than the blue color filter does. Accordingly, ifliquid crystals 310 in the pixel PX including a red or green colorfilter are controlled at two or more tilt angles, transmittance may bereduced. In addition, blue color contributes to color reproduction lessthan red and green colors do. Accordingly, if liquid crystals 310 in thepixel PX including a blue color filter are controlled at two or moretilt angles, a reduction in transmittance may be reduced to lesserextent.

In addition, if liquid crystals 310 in the pixel PX including a bluecolor filter are controlled at two or more tilt angles, the visibilitywhen skin color is produced may be increased, compared to liquidcrystals 310 in the pixel PX including a red or green color filter beingcontrolled at two or more tilt angles. Experiments for supporting sucheffects will be described in detail below.

The overcoat layer 440 may be disposed on the light-blocking element 420and the color filter layer. For example, the overcoat layer 440 may bedisposed under the light blocking element 420 and the color filter. Theovercoat layer 440 may reduce level difference between thelight-blocking element 420 and the color filter layer. In an exemplaryembodiment of the present inventive concept, the overcoat layer 440 maybe omitted.

The common electrode 480 may be disposed on the overcoat layer 440. Forexample, the common electrode 480 may be disposed on the liquid crystallayer 300. If there is no overcoat layer 440, the common electrode 480may be disposed on the light-blocking element 420 and the color filterlayer. The common electrode 480 may be made of, for example, atransparent conductive material such as indium tin oxide (ITO), indiumzinc oxide (IZO), indium tin zinc oxide (ITZO), and/or Al-doped zincoxide (AZO). The common electrode 480 may be formed throughout theentire surface of the second base substrate 410. A common signal may beapplied to the common electrode 480 such that the common electrode 480may form an electric field along with the first pixel electrode 283, thesecond pixel electrode 284, the first sub-pixel electrode 285 and thesecond sub-pixel electrode 286.

The second alignment layer 490 may be disposed on the common electrode480. For example, the second alignment layer 490 may be disposed underthe common electrode 480. The second alignment layer 490 may perform asimilar functionality with the first alignment layer 290 describedabove. For example, the second alignment layer 490 may control aninitial orientation of the liquid crystals 310 injected into theliquid-crystal layer 300.

Hereinafter, the liquid-crystal layer 300 will be described.

The liquid-crystal layer 300 may include liquid crystals 310 havingdielectric anisotropy and refractive anisotropy. The liquid crystals 310may be vertically aligned between the array substrate 200 and theopposing substrate 400 when no electric field is applied across thearray substrate 200 and the opposing substrate 400. When electric fieldis applied across the array substrate 200 and the opposing substrate400, the liquid crystals 310 may be rotated in a particular directionbetween the array substrate 200 and the opposing substrate 400 tothereby transmit or block light. For example, the liquid crystals 310may be horizontally aligned.

FIG. 4 is a view schematically showing pixel units according to anexemplary embodiment of the inventive concept.

FIG. 4 shows a total of four pixel units. In FIG. 4, a pixel unitdisposed on the upper left side is referred to as a first pixel unitPXU1, a pixel unit disposed on the upper right side (e.g., adjacent tothe first pixel unit PXU1) is referred to as a second pixel unit PXU2, apixel unit disposed on the lower left side (e.g., below the first pixelunit PXU1) is referred to as a third pixel unit PXU3, and a pixel unitdisposed on the lower right side (e.g., below the second pixel unitPXU2) is referred to as a fourth pixel unit PXU4. Each of the first tofourth pixel units PXU1, PXU2, PXU3 and PXU4 may have substantially thesame shape and structure.

Referring to FIG. 4, each of the first to fourth pixel units PXU1, PXU2,PXU3 and PXU4 includes a first pixel PX1 for producing red color, asecond pixel PX2 for producing green color, and a third pixel PX3 forproducing blue color.

Each of the first pixel PX1, the second pixel PX2 and the third pixelPX3 may have a substantially rectangular shape. As the first to thirdpixels PX1, PX2 and PX3 have a rectangular shape, each of first tofourth pixel units PXU1, PXU2, PXU3 and PXU4 formed by connecting thefirst to third pixels PX1, PX2 and PX3 may also have a substantiallyrectangular shape.

The third pixel PX3 for producing blue color may include a highgrayscale area PX3 h in which a relatively bright grayscale ispresented, and a low grayscale area PX3 l in which a relatively darkgrayscale is presented. The first sub-pixel electrode 285 shown in FIG.2 may be disposed in the high grayscale area PX3 h. The second sub-pixelelectrode 286 shown in FIG. 2 may be disposed in the low grayscale areaPX3 l. For example, the low grayscale area PX3 l may have grayscalevalues ranging between 0 and 127, and the high grayscale area PX3 h mayhave grayscale values ranging between 128 and 255. However, exemplaryembodiments of the present inventive concept are not limited thereto.

FIG. 5 is a graph showing brightness versus grayscale level of an LCDdevice according to an exemplary embodiment of the present inventiveconcept.

In FIG. 5, the x-axis represents grayscale, and the y-axis representsactually observed brightness. The minimum level of the grayscale may bezero, while the maximum level of the grayscale may be 256. When the LCDdevice was viewed from the front, the brightness at the grayscale levelof 256 was set to 1.

The lines L1 to L3 represent brightness at different grayscale levelswhen the LCD device was viewed from the front. The lines L4 to L7represent brightness at different grayscale levels when the LCD devicewas viewed from the side at forty-five degrees.

In addition, the first and fourth lines L1 and L4 are measured for apixel PX for producing red color. The second and fifth lines L2 and L5are measured for a pixel PX for producing green color. The third, sixthand seventh lines L3, L6 and L7 are measured for a pixel PX forproducing blue color.

The first to sixth lines L1, L2, L3, L4, L5 and L6 represent brightnessversus grayscale when the pixel PX includes one pixel electrode. Theseventh line L7 represents brightness versus grayscale when the pixel PXincludes the two sub-pixel electrodes 285 and 286.

It can be seen from FIG. 5 that the fourth to seventh lines L4 to L7measured when viewed from the side look brighter than the first to thirdlines L1 to L3 measured when viewed from the front at the same grayscalelevels. Such difference in brightness between the front and side maydegrade image visibility.

Nonetheless, it is observed that the seventh line L7 is closer to thesixth line L6 than the third line L3 is. Accordingly, it can be seenthat the visibility may be increased when the pixel PX includes twosub-pixel electrodes compared to when the pixel PX includes only onepixel electrode.

FIG. 6 is an xy chromaticity diagram showing color gamut of aliquid-crystal display (LCD) device according to an exemplary embodimentof the present inventive concept.

FIG. 6 shows the color gamut of the LCD device according to theexemplary embodiment of the present inventive concept by using xy colorchromaticity diagram of the XYZ colorimetric system adopted by theCommission International de l'eclairage (CIE).

The CIE area A1 is a color space defined by the Commission Internationalde l'eclairage and represents all colors in the natural world.

Triangle A2 depicted in CIE area A1 represents the color gamut of theLCD device according to an exemplary embodiment of the present inventiveconcept.

Each vertex of the triangle A2 corresponds to a brightest possible valuefor red, green and blue colors of that chromaticity, respectively. Forexample, the first point P1 represents pure red color, the second pointP2 represents pure green color, and the third point P3 represents pureblue color.

The fourth to twelfth points P4 to P12 were measured under theconditions, respectively, as indicated in the table below:

TABLE 1 Front Each of the red, green Skin color Fourth point (P4) andblue pixels includes Red color Fifth point (P5) one pixel electrodeGreen color Sixth point (P6) Side Each of the red, green Skin colorSeventh point (P7) and blue pixels includes Red color Eighth point (P8)one pixel electrode Green color Ninth point (P9) Each of the red andSkin color Tenth point (P10) includes one pixel Red color Eleventh point(P11) electrode while the Green Twelfth point (P12) blue pixel includestwo sub-pixel electrodes

According to the relationship shown in Table 1, the seventh to ninthpoints P7, P8 and P9 measured at the side are moved closer toward thewhite point WP representing white color than the fourth to sixth pointsP4, P5 to P6 measured at the front are. For example, the side may beviewed brighter than the front, such that the visibility may bedegraded.

However, the tenth to the twelfth points P10, P11 and P12 measured atthe side when each of the red and green pixels PX includes one pixelelectrode while the blue pixel PX includes two sub-pixel electrode aremoved toward the white point WP less than the seventh to ninth pointsP7, P8 and P9 measured at the side when each of the red, green and bluepixels PX includes one electrode.

In addition, the visibility may be increased when skin color isreproduced more than when red color is reproduced or when the greencolor is reproduced (e.g., the difference between the seventh point P7and the tenth point P10 is larger than the difference between the eighthpoint P8 and the eleventh point P11 or the difference between the ninthpoint P9 and the twelfth point P12). Accordingly, it can be seen thatvisibility may be increased when skin color is reproduced.

For example, it can be seen that the visibility may be increased wheneach of the red and green pixels PX includes only one pixel electrodewhile the blue pixel PX includes two sub-pixel electrodes. In addition,it may be seen that the visibility may be increased when skin color isreproduced.

FIG. 7 is a layout diagram of a single pixel disposed in a display panel100 according to an exemplary embodiment of the present inventiveconcept.

In the following description, the same or similar elements will bedenoted by the same or similar reference numerals, and redundantdescriptions may be omitted or briefly described.

Referring to FIG. 7, a single pixel unit PXU_a includes first to thirdpixels PX1_a, PX2_a and PX3_a. A first color filter 431 for producing ared color may be disposed in the first pixel PX1_a. A second colorfilter for producing a green color may be disposed in the second pixelPX2_a. A third color filter for producing blue color may be disposed inthe third pixel PX3_a.

Unlike an exemplary embodiment of the present inventive concept shown inFIG. 2 where the second sub-pixel electrode 286 surrounds the firstsub-pixel electrode 285, a first sub-pixel electrode 585 may beseparated from a second sub-pixel electrode 586 in the third pixelPX3_a, according to an exemplary embodiment of the present inventiveconcept. For example, the first sub-pixel electrode 585 may be disposedin a first area AR1 having a rectangular shape, and the second sub-pixelelectrode 586 may be disposed in a second area AR2 having a rectangularshape. The second area AR2 may be parallel to the first area AR1.Further, a gate line 224, the first to third thin-film transistorsTR1_a, TR2_a and TR3_a of the third pixel PX3_a, and first and secondcontact holes 581 and 582 may be disposed between the first area AR1 andthe second area AR2.

Accordingly, the first thin-film transistor TR1_a disposed in the firstpixel PX1_a may be disposed along a side of a first pixel electrode 583,and the second thin-film transistor TR1_a disposed in the second pixelPX2_a may be disposed along a side of a second pixel electrode 584.However, the first to third thin-film transistors TR1_a, TR2_a and TR3_adisposed in the third pixel PX3_a may be disposed between the firstsub-pixel electrode 585 and the second sub-pixel electrode 586. Thefirst thin-film transistor TR1_a of the first pixel PX1_a, the firstthin-film transistor TR1_a of the second pixel PX2_a, and the first tothird thin-film transistors TR1_a, TR2_a and TR3_a of the third pixelPX3_a may be connected to the same gate line 224, and thus may beparallel to one another. Accordingly, the overall shape of the pixelunit PXU_a might not be a rectangular shape.

For example, each of the first pixel PX1_a, the second pixel PX2_a andthe third pixel PX3_a may be disposed in an area of the single pixelunit PXU_a that has a rectangular shape. Further, the first pixel PX1_aand the second pixel PX2_a may be adjacent to each other and may bedisposed in a generally rectangular shape. However, the third pixelPX3_a disposed adjacent to the second pixel PX2_a may be dislocated withthe second pixel PX2_a. For example, the third pixel PX3 might not bealigned with the second pixel PX2_a. Accordingly, the overall shape ofthe pixel unit PXU_a including the first to third pixels PX1_a, PX2_aand PX3_a might not be a rectangular shape, but may have a shape of tworectangles dislocated (e.g., misaligned) with each other.

Additional descriptions thereof will be given with reference to FIG. 8.

FIG. 8 is a view schematically showing pixel units of an exemplaryembodiment of the present inventive concept shown in FIG. 7.

FIG. 8 shows a total of four pixel units. In FIG. 8, a pixel unitdisposed on the upper left side may be referred to as a first pixel unitPXU1_a, a pixel unit disposed on the upper right side (e.g., adjacentthe first pixel unit PXU1_a) may be referred to as a second pixel unitPXU2_a, a pixel unit disposed on the lower left side (e.g., below thefirst pixel unit PXU1_a) may be referred to as a third pixel unitPXU3_a, and a pixel unit disposed on the lower right side (e.g., belowthe second pixel unit PXU2_a) may be referred to as a fourth pixel unitPXU4_a. Each of the first to fourth pixel units PXU1_a, PXU2_a, PXU3_aand PXU4_a may have substantially the same shape and structure.

Referring to FIG. 8, each of the first to fourth pixel units PXU1_a,PXU2_a, PXU3_a and PXU4_a includes a first pixel PX1_a for producing redcolor, a second pixel PX2_a for producing green color, and a third pixelPX3_a for producing blue color.

Each of the first pixel PX1_a, the second pixel PX2_a and the thirdpixel PX3_a may have a substantially rectangular shape. The first pixelPX1_a may be parallel with the second pixel PX2_a, while the third pixelPX3_a may be dislocated with the second pixel PX2_a. Therefore, theoverall shape of each of the first to fourth pixel units PXU1_a, PXU2_a,PXU3_a and PXU4_a may have the shape of two adjacent rectanglesdislocated with respect to each other. As the first to fourth pixelunits PXU1_a, PXU2_a, PXU3_a and PXU4_a have substantially the sameshape, the first to fourth pixel units PXU1_a, PXU2_a, PXU3_a and PXU4_amay be arranged in a matrix in the display area DA of the display panel100.

To drive the first to fourth pixel units PXU1_a, PXU2_a, PXU3_a andPXU4_a, two gate lines may be disposed such that they are extended inthe first direction D1, and three data lines may be disposed such thatthey are extended in the second direction D2.

Only the third pixel PX3_a for producing blue color may include a highgrayscale area PX3 h_a in which relatively bright grayscale may bepresented, and a low grayscale area PX3 l_a in which relatively darkgrayscale may be presented. Further, the first sub-pixel electrode 585shown in FIG. 7 may be disposed in the high grayscale area PX3 h a.Further, the second sub-pixel electrode 586 shown in FIG. 2 may bedisposed in the low grayscale area PX3 l_a.

Although the high grayscale area PX3 h_a is disposed above the lowgrayscale area PX3 l_a in an exemplary embodiment of the presentinventive concept, this is merely illustrative of one possible approach.For example, the low grayscale area PX3 l_a may be disposed above thehigh grayscale area PX3 h_a in an exemplary embodiment of the presentinventive concept. The location of the high grayscale area PX3 h_a andthe low grayscale area PX3 l_a may be determined based on theirrespective areas. For example, since it is desired that the overallshape of a single pixel unit PXU has a rectangular shape, the highgrayscale area PX3 h_a may be disposed above the low grayscale area PX3l_a if the high grayscale area PX3 h_a is larger than the low grayscalearea PX3 l_a. In addition, the low grayscale area PX3 l_a may bedisposed above the high grayscale area PX3 h_a if the low grayscale areaPX3 l_a is larger than the high grayscale area PX3 h_a

FIG. 9 is a layout diagram of a single pixel disposed in a display panelaccording to an exemplary embodiment of the present inventive concept.FIG. 10 is a view schematically showing pixel units of an exemplaryembodiment of the present inventive concept shown in FIG. 9.

An exemplary embodiment of the present inventive concept will bedescribed while focusing on elements that may be different from those ofexemplary embodiments of the present inventive concept shown in FIGS. 2and 4.

Unlike the pixel units PXUs including the first to third pixels PX1, PX2and PX3 shown in FIGS. 2 and 4, the pixel unit PXU_b, according to anexemplary embodiment of the present inventive concept shown in FIGS. 9and 10, may include first to fourth pixels PX1_b, PX2_b, PX3_b andPX4_b.

In addition, in the pixel unit PXU shown in FIGS. 2 and 4, each of thefirst pixel PX1 and the second pixel PX2 includes the first thin-filmtransistor TR1, and the third pixel PX3 includes the first to thirdthin-film transistors TR1, TR2 and TR3. In contrast, in the pixel unitPXU_b according to an exemplary embodiment of the present inventiveconcept shown in FIGS. 9 and 10, all of the first to fourth pixelsPX1_b, PX2_b, PX3_b and PX4_b include a first thin-film transistor TR1_bonly.

Accordingly, the pixel unit PXU shown in FIGS. 2 and 4 may be connectedto three data lines 267, one gate line 224 and one storage line 268 todrive the first to third pixels PX1, PX2 and PX3. The pixel unit PXU_bshown in FIGS. 9 and 10 may be driven with two data lines 667 and twogate lines 624.

For example, the pixel unit PXU_b, according to an exemplary embodimentof the present inventive concept, may include a first pixel PX1_bdisposed on the upper left side, a second pixel PX2_b disposed on theupper right side (e.g., adjacent the first pixel PX1_b), a third pixelPX3_b disposed on the lower left side (e.g., below the first pixelPX1_b), and a fourth pixel PX4_b disposed on the lower right side (e.g.,below the second pixel PX2_b). For example, the first to fourth pixelsPX1_b, PX2_b, PX3_b and PX4_b may be arranged in a two-by-two matrix.

The first pixel PX1_b may include a first pixel electrode 683. Thesecond pixel PX2_b may include a second pixel electrode 684. The thirdpixel PX3_b may include a third pixel electrode 685. The fourth pixelPX4_b may include a fourth pixel electrode 686. For example, each of thefirst to fourth pixels PX1_b, PX2_b, PX3_b and PX4_b may include only asingle pixel electrode, e.g., the first to fourth pixel electrodes 683,684, 685 and 686.

In the first pixel PX1_b, a first color filter 431 may be disposed suchthat it overlaps the first pixel electrode 683. In the second pixelPX2_b, a second color filter may be disposed such that it overlaps thesecond pixel electrode 684. In the third and fourth pixels PX3_b andPX4_b, a third color filter may be disposed such that it overlaps thethird pixel electrode 685 and the fourth pixel electrode 686.

The first color filter 431 may be a red color filter that allows a lightpassing therethrough providing a red color. The second color filter maybe a green color filter that allows a light passing therethrough toprovide a green color. The third color filter may be a blue color filterthat allows a light passing therethrough to provide a blue color.

However, exemplary embodiments of the present inventive concept are notlimited thereto. For example, the first color filter 431 may be a greencolor filter, and the second color filter may be a red color filter. Thethird color filter may be a blue color filter that is disposed acrossthe third pixel PX3_b and the fourth pixel PX4_b.

While the first pixel PX1_b produces a red color and the second pixelPX2_b produces a green color, both of the third pixel PX3_b and thefourth pixel PX4_b produce a blue color. Therefore, a ratio of an areaof the first pixel PX1_b, an area of the second pixel PX2_b, and a sumof an area of the third pixel PX3_b and an area the fourth pixel PX4_bmay be adjusted. Accordingly, in the pixel unit PXU_b, the area occupiedby the first pixel PX1_b, the area occupied by the second pixel PX2_b,and the sum of the area occupied by the third pixel PX3_b and the areaoccupied by the fourth pixel PX4_b may be equal to one another.

Even though the third pixel PX3_b and the fourth pixel PX4_b bothproduce blue color, one of the third pixel PX3_b and the fourth pixelPX4_b may produce blue color of relatively bright grayscale and theother pixel may produce blue color of relative dark grayscale.

For example, the blue color produced by the third pixel PX3_b may bebrighter than that of the fourth pixel PX4_b. In this case, the voltageapplied to the third pixel electrode may be larger than the voltageapplied to the fourth pixel electrode.

Further, the first pixel PX1_b produces red color, the second pixelPX2_b produces green color, the third pixel PX3_b produces relativelybright blue color, and the fourth pixel PX4_b produces relatively darkblue color, such that the visibility may be increased.

Since the blue color may be produced at two grayscales, a reduction intransmittance may be reduced to a lesser extent than compared to whenred color and green color are produced at two grayscales each.

In addition, since only the blue color is produced at two grayscales,the visibility may be increased when skin color is reproduced.

Further, for the pixel unit PXU shown in FIGS. 2 and 4, the areaoccupied by the second sub-pixel electrode 286 may be equal to or largerthan that of the first sub-pixel electrode 285, to increase visibility.In addition, for the pixel unit PXU_b according to an exemplaryembodiment of the present inventive concept, there is no particularlimit on the areas occupied by the third pixel electrode and the fourthpixel electrode. This is because the third pixel PX3_b and the fourthpixel PX4_b of the pixel unit PXU_b, according to an exemplaryembodiment of the present inventive concept shown in FIG. 9, may becontrolled by different data lines 667, respectively. However, the firstsub-pixel electrode 285 and the second sub-pixel electrode 286 shown inFIGS. 2 and 4 may be controlled by the single data line 267.

For example, the voltage applied to the third pixel PX3_b and thevoltage applied to the fourth pixel PX4_b may be set by the data driver120. Accordingly, the areas occupied by the third pixel electrode 685may be substantially equal to the area occupied by the fourth pixelelectrode 686, and thus the area occupied by the third pixel PX3_b maybe equal to the area occupied by the fourth pixel PX4_b.

FIG. 11 is a layout diagram of a single pixel disposed in a displaypanel according to an exemplary embodiment of the present inventiveconcept.

An exemplary embodiment of the present inventive will be described whilefocusing on elements that are different from those of an exemplaryembodiment of the present inventive concept shown in FIG. 9.

Unlike the pixel unit PXU_b shown in FIG. 9, a pixel unit PXU_c,according to an exemplary embodiment of the present inventive concept,shown in FIG. 11 includes first to fourth pixels PX1_c, PX2_c, PX3_c andPX4_c that may be controlled by two data lines 767 extended in thesecond direction D2, and two gate lines 724 extended in the firstdirection D1. In this case, the third pixel PX3_c and the fourth pixelPX4_c, which are for producing blue color, may be connected to differentgate lines 724.

Accordingly, the first pixel PX1_c for producing red color may bedisposed on the upper left side. The second pixel PX2_c for producinggreen color may be disposed on the lower left side. The third pixelPX3_c for producing relatively bright blue color may be disposed on theupper right side. The fourth pixel PX4_c for producing relatively darkblue color may be disposed on the lower right side.

For example, compared to an exemplary embodiment of the presentinventive concept shown in FIG. 9, the directions in which the gatelines 724 and the data lines 767 are extended may be changed, andaccordingly the arrangement of the first to fourth pixels PX1_c, PX2_c,PX3_c and PX4_c may be changed.

With the arrangement shown in FIG. 11, the effects of increasing thevisibility overall, and increasing the transmittance and increasing thevisibility when skin color is reproduced may be achieved as in anexemplary embodiment of the present inventive concept shown in FIGS. 9and 10.

The effects of the present inventive concept are not limited by theforegoing, and other various effects are anticipated herein.

While the present inventive concept has been shown and described withreference to the exemplary embodiments thereof, it will be apparent tothose of ordinary skill in the art that various changes in form anddetail may be made thereto without departing from the spirit and scopeof the present inventive concept.

What is claimed is:
 1. A liquid-crystal display (LCD) device comprising:a first substrate; a plurality of pixel units disposed on the firstsubstrate; a color filter layer overlapping the plurality of pixel unitsand comprising first to third color filters; a second substrate facingthe first substrate; and a liquid-crystal layer interposed between thefirst substrate and the second substrate, wherein each of the pixelunits of the plurality of the pixel units comprises a first pixel, asecond pixel and a third pixel, wherein the first pixel comprises afirst pixel electrode, the second pixel comprises a second pixelelectrode, and the third pixel comprises a first sub-pixel electrode anda second sub-pixel electrode, wherein the first sub-pixel electrodeoverlaps the first pixel and second pixel, and the second sub-pixelelectrode does not overlap either the first or second pixels, whereinthe first color filter overlaps the first pixel electrode, the secondcolor filter overlaps the second pixel electrode, and the third colorfilter overlaps each of the first sub-pixel electrode and the secondsub-pixel electrode, wherein a voltage applied to the first sub-pixelelectrode is different from a voltage applied to the second sub-pixelelectrode, and wherein each of the first pixel, the second pixel and thethird pixel has substantially the same area.
 2. The LCD device of claim1, wherein the first color filter is a red color filter, the secondcolor filter is a green color filter, and the third color filter is ablue color filter.
 3. The LCD device of claim 1, wherein the first pixelcomprises a first switching element for controlling the first pixel, thesecond pixel comprises a second switching element for controlling thesecond pixel, the third pixel comprises a third switching element forcontrolling the third pixel, and the first to third switching elementsare arranged in parallel with one another.
 4. The LCD device of claim 3,wherein the first sub-pixel electrode is disposed in a first area havinga rectangular shape, the second sub-pixel electrode is disposed in asecond area having a rectangular shape, and the second area is disposedadjacent to the first area.
 5. The LCD device of claim 4, wherein thefirst switching element is disposed at a side of the first pixelelectrode, the second switching element is disposed at a side of thesecond pixel electrode, and the third switching element is disposedbetween the first area and the second area.
 6. The LCD device of claim3, wherein the area occupied by the first pixel electrode issubstantially equal to the area occupied by the second pixel electrode,and the area occupied by the first pixel electrode is equal to or largerthan a sum of the area occupied by the first sub-pixel electrode and thearea occupied by the second sub-pixel electrode.
 7. The LCD device ofclaim 3, further comprising: a gate line disposed on the first substrateand carrying a gate signal; a first, a second and a third data linedisposed on the first substrate and carrying a data signal; and astorage line disposed on the first substrate and carrying a storagesignal, wherein the first switching element comprises a first thin-filmtransistor connected to each of the gate line, the first data line andthe first pixel electrode, the second switching element comprises asecond thin-film transistor connected to each of the gate line, thesecond data line and the second pixel electrode, and the third switchingelement comprises a third thin-film transistor connected to each of thegate line, the third data line and the first sub-pixel electrode, afourth thin-film transistor connected to each of the gate line, thethird data line and the second sub-pixel electrode, and a fifththin-film transistor connected to each of the gate line, the storageline and the second sub-pixel electrode.
 8. The LCD device of claim 1,wherein each of the first pixel and the second pixel comprises a singlecontact hole, and the third pixel comprises two contact holes.
 9. Aliquid-crystal display (LCD) device comprising: a first substrate; aplurality of pixel units disposed on the first substrate; a color filterlayer overlapping the plurality of pixel units and comprising first tothird color filters; a second substrate facing the first substrate; anda liquid-crystal layer interposed between the first substrate and thesecond substrate, wherein each of the pixel units of the plurality ofthe pixel units comprises a first pixel, a second pixel and a thirdpixel, wherein the first pixel comprises a first pixel electrode, thesecond pixel comprises a second pixel electrode, and the third pixelcomprises a first sub-pixel electrode and a second sub-pixel electrode,wherein the first color filter overlaps the first pixel electrode, thesecond color filter overlaps the second pixel electrode, and the thirdcolor filter overlaps each of the first sub-pixel electrode and thesecond sub-pixel electrode, wherein a voltage applied to the firstsub-pixel electrode is different from a voltage applied to the secondsub-pixel electrode, and wherein each of the first pixel, the secondpixel and the third pixel has substantially the same area, wherein thefirst pixel comprises a first switching element for controlling thefirst pixel, the second pixel comprises a second switching element forcontrolling the second pixel, the third pixel comprises a thirdswitching element for controlling the third pixel, and the first tothird switching elements are arranged in parallel with one another,wherein the first sub-pixel electrode is disposed in a first area havinga rectangular shape, the second sub-pixel electrode is disposed in asecond area having a rectangular shape, and the second area is disposedadjacent to the first area, wherein each of the first to third pixels isdisposed in a rectangular area of a pixel unit of the plurality of pixelunits, and the third pixel is disposed between the first pixel and thesecond pixel, wherein the third pixel is misaligned with the secondpixel.
 10. The LCD device of claim 9, wherein the first color filter isa red color filter, the second color filter is a green color filter, andthe third color filter is a blue color filter.
 11. The LCD device ofclaim 9, wherein the first switching element is disposed at a side ofthe first pixel electrode, the second switching element is disposed at aside of the second pixel electrode, and the third switching element isdisposed between the first area and the second area.
 12. The LCD deviceof claim 9, wherein the area occupied by the first pixel electrode issubstantially equal to the area occupied by the second pixel electrode,and the area occupied by the first pixel electrode is equal to or largerthan a sum of the area occupied by the first sub-pixel electrode and thearea occupied by the second sub-pixel electrode.
 13. The LCD device ofclaim 9, further comprising: a gate line disposed on the first substrateand carrying a gate signal; a first, a second and a third data linedisposed on the first substrate and carrying a data signal; and astorage line disposed on the first substrate and carrying a storagesignal, wherein the first switching element comprises a first thin-filmtransistor connected to each of the gate line, the first data line andthe first pixel electrode, the second switching element comprises asecond thin-film transistor connected to each of the gate line, thesecond data line and the second pixel electrode, and the third switchingelement comprises a third thin-film transistor connected to each of thegate line, the third data line and the first sub-pixel electrode, afourth thin-film transistor connected to each of the gate line, thethird data line and the second sub-pixel electrode, and a fifththin-film transistor connected to each of the gate line, the storageline and the second sub-pixel electrode.
 14. The LCD device of claim 9,wherein each of the first pixel and the second pixel comprises a singlecontact hole, and the third pixel comprises two contact holes.
 15. Aliquid-crystal display (LCD) device comprising: a first substrate; aplurality of pixel units disposed on the first substrate; a color filterlayer overlapping the plurality of pixel units and comprising first tothird color filters; a second substrate facing the first substrate; anda liquid-crystal layer interposed between the first substrate and thesecond substrate, wherein each of the pixel units of the plurality ofthe pixel units comprises a first pixel, a second pixel and a thirdpixel, wherein the first pixel comprises a first pixel electrode, thesecond pixel comprises a second pixel electrode, and the third pixelcomprises a first sub-pixel electrode and a second sub-pixel electrode,wherein the first color filter overlaps the first pixel electrode, thesecond color filter overlaps the second pixel electrode, and the thirdcolor filter overlaps each of the first sub-pixel electrode and thesecond sub-pixel electrode, wherein a voltage applied to the firstsub-pixel electrode is different from a voltage applied to the secondsub-pixel electrode, and wherein each of the first pixel, the secondpixel and the third pixel has substantially a same area, wherein each ofthe first pixel electrode and the second pixel electrode are disposed ina separate first area having a rectangular shape, the first sub-pixelelectrode and the second sub-pixel electrode are disposed in a secondarea having a rectangular shape, and the first area and the second areahave a shape of two rectangles dislocated with each other.